129563281 has 2 divisors, whose sum is σ = 129563282. Its totient is φ = 129563280.

The previous prime is 129563279. The next prime is 129563297. The reversal of 129563281 is 182365921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91011600 + 38551681 = 9540^2 + 6209^2 .

It is an emirp because it is prime and its reverse (182365921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129563281 - 2¹ = 129563279 is a prime.

It is a super-2 number, since 2×129563281² = 33573287566969922, which contains 22 as substring.

Together with 129563279, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129563281.

It is not a weakly prime, because it can be changed into another prime (129563221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64781640 + 64781641.

It is an arithmetic number, because the mean of its divisors is an integer number (64781641).

Almost surely, 2^129563281 is an apocalyptic number.

It is an amenable number.

129563281 is a deficient number, since it is larger than the sum of its proper divisors (1).

129563281 is an equidigital number, since it uses as much as digits as its factorization.

129563281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 37.

The square root of 129563281 is about 11382.5867446728. The cubic root of 129563281 is about 506.0118014506.

The spelling of 129563281 in words is "one hundred twenty-nine million, five hundred sixty-three thousand, two hundred eighty-one".